Questions tagged [electrical-system]
The parts of an aircraft that produce electrical power (such as generators/alternators, batteries, and ram air turbines) and distribute it to the aircraft's systems.
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How are fly-by-wire airliners controlled in case of complete electrical failure?
In this comment, it is postulated that even fly-by-wire aircraft (Airbus) are demonstrated to fly without any electrical systems:
All Airbus aircraft are demonstrated controllable with complete ...
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Why do airplanes use AC electric power?
Primary electric power on larger airplanes is provided as AC. What aspects of aircraft make AC a better choice than DC?
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Where is the generator in a large turbofan of a commercial airliner?
So, where do you put the electrical generator?
If it's gonna be coaxial, the only place is the rear (it will be burnt) or the front (it will get in the way of intake).
If it's gonna be coupled to a ...
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What are the hurdles to overcome before purely electric commercial aircraft can fly?
What are currently the largest issues with purely electric commercial aircraft (large scale ones like the size of a Boeing 737)?
Are there any organizations right now that are trying to solve those ...
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How does the A350/380 operate on Variable Frequency AC generators?
To keep a constant frequency of 400 Hz, most aircraft have a CSD (Constant Speed Drive) associated to the AC generator. On most types (e.g. A320, A330, B737, B747, B777) an Integrated Drive Generator (...
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Is aluminum electrical wire used on aircraft?
Aluminum electrical wire got a bit of a bad reputation in household wiring due to reacting badly with terminals not properly rated for aluminum. Properly handled, it works fine, but it's so ...
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Why do aircraft use 400 Hz AC instead of the 50 or 60 Hz of wall outlets? [duplicate]
Large aircraft electrical systems usually use 400 Hz alternating current (AC), while common household electrical outlets deliver AC at 50 or 60 Hz. Why the difference?
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How much electrical power does one generator produce on a large turbofan?
From my related question, now I want to know just how much power does the generator produce? In other words, what is the max rating of the generator? It looks so small and that surprised me, but since ...
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Can rotorcraft pick up a dangerous electric charge?
So, I was re-watching The Hunt For Red October, (in light of current Russian shenanigans with Sweden), and there was a scene in which a crew-member on the ground was electrocuted by making contact (...
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What powers an aircraft prior to the APU being switched on?
I know that APUs are power plants for non-propulsion related purposes and that they are turned on before takeoff.
What powers an airplane prior to the APU being turned on?
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Where are the circuit breakers on the 787?
(787 left, 777 right)
Normally found aft of the overhead panel, where are they on the Boeing 787?
user14897
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What is the process to disconnect ground electric power before pushback?
While commercial airliner are parked at the gate, they have electrical power connected to the aircraft (if available at the airport). This needs to be disconnected before pushback - what is the ...
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Will the landing gear work mechanically in case of total power loss?
In case of a total power failure in all the aircraft systems like engine failure and APU failure, would it be possible to use mechanical means (manually) to open the landing gear bay door and deploy ...
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Are parked airliners always connected to a ground power unit?
I'm wondering if commercial passenger planes, like the A320, are always connected to the ground power unit (GPU) when they are at the gate? Even if for a quick turnaround.
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Why do jet generators produce a higher frequency power then household electricity? [duplicate]
I know in most homes your local transformer provides a 50Hz or 60Hz power source. So all your hairdryers, dishwashers etc. are built to consume 50Hz or 60Hz power at 110 volts or 220 volts, ...
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Would "wind turbine generators" in the bypass stream save fuel for jetliners?
What is the location of an aircraft's alternator, in a large airliner like a Boeing 747 or Airbus A380?
How much power does it produce in kilowatts?
And what is the possibility of installing it with ...
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Why is Hydrazine used to power the F-16's EPU?
Why does the military use hydrazine to power the F-16's Emergency Power Unit (EPU)? What is so unique about Hydrazine fuel that it's needed to power the EPU? Why not use a less volatile and less ...
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Does electrical usage contribute to fuel consumption?
I know that while in-flight the electricity is produced by the engines.
What happens if every possible system requiring electricity is in the on state? This should ...
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What happens when disengaging the electricity generators on a B747?
This answer says:
If let's say, you [...] disengage the electricity generator of every engine (which cannot be re-engaged without mechanical maintenance), [...].
What exactly happens in the ...
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Are there commercial airplanes that are still flyable without any electricity? [duplicate]
I have seen the first episode of Revolution yesterday and there are all kinds of airplanes just falling from the sky because of complete loss of electricity.
I know most if not all modern planes use ...
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Why use a RAT when engines can windmill?
When a dual engine flame-out is encountered, and the engines themselves are not damaged such as in the case of Air Transat Flight 236, why is the RAT deployed for emergency power instead of using the ...
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What's the plug used on airliners for ground power?
What's the plug pair called?
What's the ISO/whatever standard involved?
What do they look like close-up?
Is it pretty standard today worldwide?
Is the plug identical for the hugest airliners as for ...
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What is the shed bus in the Phenom 100?
I recently came across a part of the electrical system of aircraft named SHED BUS. I am specifically asking for the Embraer Phenom 100.
Source (Page 122), Added ...
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What is the low resistance design path in an aircraft to withstand a lightning strike?
I know in a building we have lightning rods that conduct a lightning strike into the earth, but for an aircarft there is no ground to 'ground' so I assume the lightning enters and passes through the ...
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What happens with the avionics if in midair there is loss of power or fuel flow interrupted? [duplicate]
What happens if in midair there is loss of power, how will the avionics perform in such a situation (cockpit display, flight plan)?
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Is there any electrical component on an aircraft which can never be turned off by a pilot?
Am I correct to assume that every electrical system on an aircraft can be manually switched OFF/ON by the Pilot OR is there indeed any system, on which the Pilot does not have the ability to switch ...
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What could cause the APU on a Boeing 777 to fail and also trip the GPU?
I am a cargo aircraft loader at Heathrow and while we were offloading cargo, pallets and baggage containers from a Pakistan Airlines B777, the aircraft's Auxiliary Power Unit (APU) failed. It made ...
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What does BUS mean in the startup procedure?
I noticed the term BUS in the startup procedure of a 737. What do BUS on, off and transfer mean and what is their significance?
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Why are the 737's variable-speed generator drives so unreliable?
The 737 Classic has two different possible styles of engine-driven generators, distinguished by the generator's drive mechanism: the constant-speed drive (CSD) and the variable-speed constant-...
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How do electric anti-icing systems work?
How do they work for GA propeller planes? More specifically, how is it implemented on the leading edge of the wing and propeller blades? I'm more interested in the mechanics of electric heating, not ...
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Pre-50's, how was electricity generated without using an Integrated Drive Generator?
The question How do airplanes regulate the output frequency of AC generators? here on SE already answers why we need an IDG with a constant speed drive on airliners.
[IDG's] have been used in ...
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Can large airliners such as a 747 maneuver without electricity?
Small aircraft have the flight controls physically linked to control surfaces by some kind of cable and pulley system. For a large aircraft such as a 747, are the control systems mechanically aided ...
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How do airplanes regulate the output frequency of AC generators?
AC electrical buses are common in airplanes from light piston twins all the way up to the largest airliners. I usually see both a 115v and 36v AC bus with a 400 Hz output frequency. How do most ...
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How much power is used by cabin lighting systems during flight?
How much power is used by cabin lighting systems during flight when all the lights are ON?
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How much electrical power is available in a Gulfstream G550 and from which power sources?
I'd like to understand what electrical power sources are available (engines? APU? GPU? Other?) on a larger jet like the G550, and how much power they can provide, depending on whether the airplane is ...
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How do I interpret electrical system indications in a G1000 C-182?
I recently switched to a G1000 equipped aircraft C182 and trying to figure out the specifics of the G1000 and how it works in the 182.
One that I can't really figure out with the manual and the POH ...
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Why are these steps performed on the A330 emergency electrical checklist?
For an Airbus A330 in emergency electrical configuration with both generators and APU FAIL (both engines working), why does the checklist ask you to select RAT MAN ON before slat extension and then ...
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